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Abstract:

A control apparatus for controlling a laser processing machine, includes:
a HDD as data storing means for storing shape data on a shape of a
processed part to which laser processing of the laser processing machine
is applied and data on a processing condition of the laser processing
machine; and a CPU as processing condition adjusting means for performing
adjustment of the processing condition with reference to the shape data
and the data on the processing condition stored in the data storing
means. The shape data that is acquired as to a work when the work to
which the laser processing is applied is determined to be a defective
item and the data on the processing condition that is adjusted by the
processing condition adjusting means according to the determination of
being a defective item are accumulated in the data storing means in
association with each other.

Claims:

1. A control apparatus for controlling a laser processing machine,
comprising: data storing means for storing shape data on a shape of a
processed part to which laser processing of the laser processing machine
is applied, and data on a processing condition of the laser processing
machine; and processing condition adjusting means for performing
adjustment of the processing condition with reference to the shape data
and the data on the processing condition stored in the data storing
means, wherein the shape data that is acquired as to a work when the work
to which the laser processing is applied is determined to be a defective
item, and the data on the processing condition that is adjusted by the
processing condition adjusting means according to a determination of
being a defective item, are accumulated in the data storing means in
association with each other.

2. The control apparatus according to claim 1, wherein data on the
processing condition when a work to which the laser processing is applied
is determined to be a conforming item, is registered in the data storing
means.

3. The control apparatus according to claim 1, comprising adjustment
completion inputting means for accepting an input operation for
completing the adjustment by the processing condition adjusting means,
and wherein the data on the processing condition is registered in the
data storing means according to the input operation to the adjustment
completion inputting means.

4. The control apparatus according to claim 1, wherein the data storing
means further stores data on at least either one of a material and a
thickness of the work.

5. The control apparatus according to claim 1, comprising shape data
acquiring means for acquiring the shape data.

6. The control apparatus according to claim 5, wherein the shape data
acquiring means includes at least either photographing means for
photographing the processed part or surface shape measuring means for
measuring surface roughness of the processed part resulting from the
laser processing.

7. A laser processing machine comprising a control apparatus that
includes: data storing means for storing shape data on a shape of a
processed part to which laser processing of the laser processing machine
is applied, and data on a processing condition of the laser processing
machine; and processing condition adjusting means for performing
adjustment of the processing condition with reference to the shape data
and the data on the processing condition stored in the data storing
means, wherein the shape data that is acquired as to a work when the work
to which the laser processing is applied, is determined to be a defective
item and the data on the processing condition that is adjusted by the
processing condition adjusting means according to a determination of
being a defective item are accumulated in the data storing means in
association with each other.

Description:

FIELD

[0001] The present invention relates to a control apparatus and a laser
processing machine including the control apparatus.

BACKGROUND

[0002] Conventionally, when a processing defect is found in laser
processing, the processing condition is changed according to the state of
the processed part and the processing is repeated. The processing
condition is adjusted by operator's empirically-based decisions, coping
methods displayed on a processing help screen, and the like according to
the state of the processed part when the processing defect is observed.
For example, Patent Literature 1 proposes a technology on a processing
machine expertise support system which displays a list of a plurality of
change causes that represent the causes of defects, and displays all
information on selected causes of defects as a condition change list.
Changes to make are selected from the displayed condition change list,
and the settings of the processing machine are changed to resolve the
causes of the defective item.

[0004] In laser processing, a processing defect is often resolved by
adjusting two or more parameters of the processing condition. The
decisions about which parameters to select from the plurality of
parameters displayed in the list and to what extent to change the
parameters are up to the operator. Depending on the processing expertise
the operator has, a large number of trials and a lot of time may
therefore be needed before the resolution of a processing defect. The
processing accuracy required of laser processing often varies by product
type or by user. It is therefore desired that the processing condition be
also adjustable as appropriate to the processing accuracy required.

[0005] The present invention has been achieved in view of the foregoing,
and it is an object thereof to provide a control apparatus that allows
adjustment of the processing condition appropriate to a desired
processing accuracy and allows resolution of processing defects
irrespective of the level of processing expertise, and a laser processing
machine that includes the control apparatus.

Solution to Problem

[0006] In order to solve the aforementioned problems and attain the
aforementioned object, the control apparatus for controlling a laser
processing machine is provided with: data storing means for storing shape
data on a shape of a processed part to which laser processing of the
laser processing machine is applied, and data on a processing condition
of the laser processing machine; and processing condition adjusting means
for performing adjustment of the processing condition with reference to
the shape data and the data on the processing condition stored in the
data storing means, wherein the shape data that is acquired as to a work
when the work to which the laser processing is applied is determined to
be a defective item, and the data on the processing condition that is
adjusted by the processing condition adjusting means according to a
determination of being a defective item, are accumulated in the data
storing means in association with each other.

Advantageous Effects of Invention

[0007] The present invention has the effect that it is possible to adjust
the processing condition as appropriate to a desired processing accuracy
and resolve processing defects irrespective of the level of processing
expertise.

BRIEF DESCRIPTION OF DRAWINGS

[0008]FIG. 1 is a block diagram showing the configuration of a laser
processing machine according to an embodiment.

[0010]FIG. 3 is a flowchart for explaining the procedure for adjusting a
processing condition.

DESCRIPTION OF EMBODIMENTS

[0011] Hereinafter, an embodiment of the control apparatus and the laser
processing machine according to the present invention will be described
in detail with reference to the drawings. It should be noted that the
present invention is not limited by this embodiment.

Embodiment

[0012]FIG. 1 is a block diagram showing the configuration of a laser
processing machine 1 according to the embodiment of the present
invention. The laser processing machine 1 includes a processing table 2,
a control apparatus body 3, shape data acquiring means 4, and display
means 5. A plate material is placed on the processing table 2. The
control apparatus body 3, the shape data acquiring means 4, and the
display means 5 constitute a control apparatus for controlling the laser
processing machine 1.

[0013] The control apparatus body 3 includes a CPU 10, a HDD 11, and a
processing start button 12. The CPU 10 executes various types of
arithmetic processing for controlling the laser processing machine 1. The
HDD 11 being data storing means contains a database. Shape data on the
shape of processed parts to which the laser processing of the laser
processing machine 1 is applied, and data on the processing condition of
the laser processing machine 1 are registered in the database, as well as
data on work materials and data on thickness, for example.

[0014] The CPU 10 functions as processing condition adjusting means for
performing adjustment of the processing condition with reference to the
shape data, the data on the processing condition, and the like registered
in the database. The processing start button 12 accepts an input
operation for starting the laser processing of the laser processing
machine 1.

[0015] The shape data acquiring means 4 is connected to the control
apparatus body 3 through a LAN, for example.

[0016] The shape data acquiring means 4 is intended to acquire shape data
on the shape of a processed part, and includes photographing means 13 and
surface shape measuring means 14. The photographing means 13 is a camera
for photographing a processed part. The surface shape measuring means 14
measures the surface roughness of a surface processed by the laser
processing. For example, the surface shape measuring means is a surface
profiler of optical scanning type. It should be noted that the shape data
acquiring means 4 has only to include at least either the photographing
means 13 or the surface shape measuring means 14.

[0017]FIG. 2 is a diagram showing a display example of the display means
5. For example, the display means 5 is a CRT display having a screen 15
that functions as a touch panel. The display example shown here is where
the measurement of the shape data acquiring means 4 is in process. A
measurement start button 16 and an adjustment completion button 17 are
displayed on the screen 15. The measurement start button 16 accepts an
input operation for starting the measurement of the shape data acquiring
means 4. The adjustment completion button 17 is adjustment completion
inputting means for accepting an input operation for completing
adjustment of the processing condition. To indicate the current status of
the laser processing machine 1, a message "MEASURING" is displayed on the
screen 15, beside the measurement start button 16 and the adjustment
completion button 17.

[0018]FIG. 3 is a flowchart for explaining the procedure for adjusting
the processing condition. In step S1, a material is set on the processing
table 2. In step S2, an NC program for laser processing is called. In
step S3, the operator presses the processing start button 12. In step S4,
laser processing is started. The laser processing is performed according
to the called NC program and a processing condition that is set as
initial values. In step S5, whether the laser processing is finished or
not is determined. If the laser processing is determined not to be
finished yet (step S5, No), the laser processing started in step S4 is
continued. If the laser processing is determined to have finished (step
S5, Yes), then in step S6, the processed work is taken out and the
operator checks the work for a processing defect.

[0019] If a processing defect is found by the checking in step S6 and the
work is determined to be a defective item (determined not to be a
conforming or good item) (step S7, No), the operator sets the work
determined to be a defective item into the shape data acquiring means 4
(step S8). In step S9, the operator presses the measurement start button
16. In step S10, the photographing means 13 performs photographing, and
the surface shape measuring means 14 performs a measurement.

[0020] Among examples of major forming failures in laser processing are
the adhesion of dross to the backside of the plate material and stripes
of asperities formed on the processed surface. The shape data acquiring
means 4 acquires data on the shape and size of dross mainly by
photographing using the photographing means 13. The shape data acquiring
means 4 also acquires data on the asperities on the processed surface
mainly by measurement using the surface shape measuring means 14. The
shape data acquiring means 4 digitizes such data into shape data.

[0021] For evaluation, the operator has only to determine whether or not
the processed item constitutes a processing defective. Which mode of
processing defects the item corresponds to is accurately and objectively
determined by the measurement by the shape data acquiring means 14. The
shape data acquired by the shape data acquiring means 4 is transmitted to
the control apparatus body 3 by network communication or serial
communication (step S11). The message "MEASURING" is displayed on the
screen 15 of the display means 5, for example, between when the shape
data acquiring means 4 starts measurement and when the transmission of
the shape data to the control apparatus body 3 is completed.

[0022] Next, the control apparatus body 3 makes an automatic correction to
the processing condition through arithmetic operations of the CPU 10
(step S12). In step S12, the data on the processing condition that is
registered in association with the material and thickness of the work
that causes the processing defect, and the shape data acquired by the
shape data acquiring means 4 are read out. The read data and the current
processing condition are compared, and corrections are made to implement
a processing condition that is best suited to the resolution of the
processing defect.

[0023] Examples of parameters of the processing condition to be adjusted
include the focal position of the laser, gas pressure, processing feed
speed, the output power of the laser, and nozzle gap. For a processing
defect of dross adhesion, corrections such as lifting the focal position,
increasing the gas pressure, and reducing the processing feed speed are
made. For a processing defect of producing stripes of asperities on the
processed surface, corrections such as lifting or lowering the focal
position and decreasing the gas pressure are made. The focal position is
changed in units of 0.5 mm, for example. Which parameters to be adjusted
to select and to what extent to change are appropriately corrected
according to the mode of the processing defect, such as the particle size
or shape in the case of dross, and the shape of stripes and the height
and intervals of asperities in the case of stripes of asperities. The
method to cope with a processing defect also varies depending on the
material and thickness. The parameters of the processing condition to be
adjusted have only to be at least one, and may be more than one. The
parameters of the processing condition to be adjusted are not limited to
those described in the present embodiment, and may be added as
appropriate.

[0024] When the correction of the processing condition is completed, then
in step S13, a message such as "CONDITION CORRECTED" is displayed on the
screen 15 of the display means 5. Next, in step S14, a material is set
again. In step S3, the operator presses the processing start button 12,
and the laser processing is started again under the adjusted processing
condition (step S4). In step S7, if the work is determined again to be a
defective item (step S7, No), the procedure of step S8 and subsequent
steps is repeated.

[0025] If, in step S7, the work is determined to be a conforming item
(step S7, Yes), then in step S15, the operator presses the adjustment
completion button 17. In response to the depression of the adjustment
completion button 17, the data on the processing condition when the work
is determined to be a conforming or good item is registered in the
database along with the shape data acquired by the shape data acquiring
means 4 (step S16). This is the end of the adjustment of the processing
condition. It should be appreciated that the data on the work material
and the data on the thickness to be registered in the database may be
those previously stored in the HDD 11 or those input on such occasions as
the beginning of processing and the beginning of measurement.

[0026] The foregoing adjustment of the processing condition is repeated on
the laser processing machine 1. As a result, shape data that is acquired
as to works when the works are determined to be a defective item and the
data on the processing condition that is adjusted by the processing
condition adjusting means according to the determination of being a
defective item, are accumulated in the data storing means in association
with each other. It should be appreciated that initial values of the data
on the processing condition and the shape data may be previously stored
in the HDD 11 before the data accumulation through the processing of the
laser processing machine 1.

[0027] Based on the data on the processing condition stored in the
database, the processing condition can be adjusted to resolve a
processing defect with a fewer number of trials and in a shorter time of
adjustment operations irrespective of the level of processing expertise
the operator has. Each time a processing defect is observed in the laser
processing, the shape data and the data on the adjusted processing
condition are accumulated. This allows adjustment of the processing
condition appropriate to a processing accuracy required of the laser
processing with respect to each product type and each user. Consequently,
there is provided an effect that it is possible to adjust the processing
condition as appropriate to a desired processing accuracy and resolve
processing defects irrespective of the level of processing expertise.

[0028] The control apparatus according to the present embodiment may be
applied to a conventional laser processing machine. The control apparatus
has only to include at least the control apparatus body 3, and may be
configured without the shape data acquiring means 4 or the display means
5.

INDUSTRIAL APPLICABILITY

[0029] As described above, the control apparatus and the laser processing
machine according to the present invention are useful in making it
possible to resolve processing defects irrespective of the level of the
operator's processing expertise.